Fountain pen



March 17, 1925.

K c. LINDEN ET AL FOUNTAIN PEN Fled'Jafn. 6, 1925 Patented Mer. 1925.

UNITED STATES PATENT OFFICE.

CHARLES LINDENl AND WALTER TRUNK, 0F SOUTH AMBO'Y, NEW JERSEY.

Applicationled January 6, 1925.' Serial No. 789.

To all whom t may concern:

Be it known that we, CHARIns LINDEN, a citizen of the United States, and WALTER TRoNK, a citien of the Republic of Germany, residing inSouth Amboy, in the county of Middlesexk and State of New Jer` sey, have invented certain new and useful Improvements in Fountain Pens, of which the following is a specification.

This invention relates to fountain pens and has for an object to provide a visual indicator of the ink reservoir so that by inspection the time for refilling can readily be determined. This invention is shown applied to the so called self filling type of fountain pens, is comparatively inexpensive and can be applied with very little change to the ordinary type of fountain pen.

The objects of the invention will be more particularly understood from the following specification and the accompanying drawings in-which, Fig. 1 is a sectionview of a fountain pen of the usual type to which our' invention has been applied, Fig. 2 is a view of the pen complete and Fig. 3 is a detail,

partly in'section, showing an alternative construction in the application of our invention. Fig. 4 is a section on the line 4-4, Fig. 3.

In the ordinary type of fountain pen the flow of'ink is often impeded and it is impossible to tell if this is due to want of ink in the reservoir or to stoppage of the ink passage. In the present invention part of the ink reservoir is transparent and suitable windows or aperturesare provided in the barrel of the pen by which the transparent part of the reservoir and thus the ink supply `is open to inspection.

In the self filling pens the ink reservoir is usually made of rubber tubing "which is easily collapsed for rellin purposes. In applying ourtinvention we ave removeda section of this rubbber tubing and substituted glass tubing therefor and opposite this glass tube a slot is milled through the barrel of the pen so that acfsight may be taken through the glass tube from which the height ofthe ink in the reservoir is determined. The slots in the barrel of the pen may be left open or theymay be protected by an outer transparent ferrule or by a rotating sleeve.

Referring to the drawings, 11 is the barrel of the pen, 12 is the stubT screwed into the barrel at 13 and 14 is the writin point. The stub 12terminates in the shari 15 and by the rubber tubing 16 connects with the glass tube 17 and the glass tube, in turn, connects with the rubber tbe 18. The tubes 16, 17

rubber tubing'maybe cemented or otherwise fastened to the rigid parts.,

The self filling lever is indicated at 22. When this lever is moved outwards theflat spring 23 compresses the tube 18 prepar'atory to drawing in a new supply of ink. This is the usual construction in pens of this type and the operation is not interfered with by the glass tube 17.

The construction in Fig. 3 shows a rotating sleeve .for covering the slots 19 and 20. This sleeve 24 is rotated by the knurled end 25 i and has a pair of diametrically opposed slots at 26 which can be brought into line with 27 and 28 and thusv expose the glass tube inl the ink reservoir.

It will be noted that when the pen is held vertically the transparent tube is near the bottom of thereservoir and thus shows when the supply of ink is low. Attention is called to the fact that by sighting the ink through the tube there-is no dark background against ing the slots 19 and 20 in the barrel and inl serting a section of reservoir. I

Having thus described our invention, we claim:

1. In a fountain the combination o a barrel having a pair glass tube inthe ink of diametrically opposed slots with a detachable ink reservoir in said barrel, a transparent section in said reservoir, said transparent section being opposite said slots.

`2. In a fountain pen of the class described, the combination of a barrel having a slot in its side with an ink reservoirin said barrel, said reservoir comprising a portion of rubn of the class described, 'i

i the combination ofqa barrel having a slot in its side, a transparent cover for said slot and a detachable ink reservoirV in said barrel, said reservoir having a transparent section opposite said slot. v e] 4. In afountain pen of the class described, the combination of a barrel having a pair of diametrically opposed slots, a ferrule for protecting said slots and a detachable ink reservoir in said barrel, said reservoir having a transparent section opposite said s1ot.

5i. a fountain pen of the .class described,

the combination of a barrel having a slot in its side, a stub secured 4to the end of said barrel and an ink reservoir secured to said stub, said reservoir comprising a section of rubber tubing, a section of glass tubingand a second section of rubber tubing closed at one end, said glass tubing being located opposite said slot. j

Signed at South Amboy, Middlesex County, New Jersey, this 31st day of October,

i CHARLES LINDEN.

WALTER TRONK. 

